Darapladib inhibits atherosclerosis development in type 2 diabetes mellitus Sprague-Dawley rat model

AbstractObjective. Increase in the low-density lipoprotein (LDL) level in diabetes mellitus and atherosclerosis is related to lipoprotein associated phospholipase A2 (Lp-PLA2). Lp-PLA2 is an enzyme that produces lysophosphatidylcholine (LysoPC) and oxidized nonesterified fatty acids (oxNEFA). LysoPC regulates inflammation mediators, including intra-cellular adhesion molecule-1 (ICAM-1). Darapladib is known as a Lp-PLA2 specific inhibitor. The aim of this study was to reveal the effect of darapladib on the foam cell number, inducible nitric oxide synthase (iNOS), and ICAM-1 expression in aorta at early stages of the atherosclerosis in type 2 diabetes mellitus Sprague-Dawley rat model.Methods. Thirty Sprague-Dawley male rats were divided into 3 main groups: control, rats with type 2 diabetes mellitus (T2DM), and T2DM rats treated with darapladib (T2DM-DP). Each group was divided into 2 subgroups according the time of treatment: 8-week and 16-week treatment group. Fasting blood glucose, insulin resistance, and lipid profile were measured and analyzed to ensure T2DM model. The foam cells number were detected using hematoxylin-eosin (HE) staining and the expression of iNOS and ICAM-1 was analyzed using double immunofluorescence staining.Results. Induction of T2DM in male Sprague-Dawley rats after high fat diet and streptozotocin injection was confirmed by elevated levels of total cholesterol and LDL and increased fasting glucose and insulin levels compared to controls after both times of treatment. Moreover, T2DM in rats induced a significant increase (p<0.05) in the foam cells number and iNOS and ICAM-1 expression in aorta compared to controls after both treatment times. Darapladib treatment significantly reduced (p<0.05) foam cells number as well as iNOS expression in aorta in rats with T2DM after both treatment times. A significant decrease (p<0.05) in ICAM-1 expression in aorta was observed after darapladib treatment in rats with T2DM only after 8 weeks of treatment.Conclusion. Our data indicate that darapladib can decrease the foam cells number, iNOS, and ICAM-1 expression in aorta at the early stages of atherosclerosis in T2DM rat model.

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The Biological Impacts of Sitagliptin on the Pancreas of a Rat Model of Type 2 Diabetes Mellitus: Drug Interactions with Metformin

Biology ◽

10.3390/biology9010006 ◽

2019 ◽

Vol 9 (1) ◽

pp. 6 ◽

Cited By ~ 1

Author(s):

Lamiaa M. Shawky ◽

Ahmed A. Morsi ◽

Eman El Bana ◽

Safaa Masoud Hanafy

Keyword(s):

Diabetes Mellitus ◽

Type 2 Diabetes ◽

Type 2 Diabetes Mellitus ◽

Rat Model ◽

Cell Damage ◽

Diabetic Rats ◽

Male Rats ◽

Control Group ◽

Dipeptidyl Peptidase 4

Sitagliptin, a dipeptidyl peptidase-4 (DPP-4) inhibitor, is a beneficial class of antidiabetic drugs. However, a major debate about the risk of developing pancreatitis is still existing. The aim of the work was to study the histological and immunohistochemical effects of sitagliptin on both endocrine and exocrine pancreases in a rat model of type 2 diabetes mellitus and to correlate these effects with the biochemical findings. Moreover, a possible synergistic effect of sitagliptin, in combination with metformin, was also evaluated. Fifty adult male rats were used and assigned into five equal groups. Group 1 served as control. Group 2 comprised of untreated diabetic rats. Group 3 diabetic rats received sitagliptin. Group 4 diabetic rats received metformin. Group 5 diabetic rats received both combined. Treatments were given for 4 weeks after the induction of diabetes. Blood samples were collected for biochemical assay before the sacrification of rats. Pancreases were removed, weighed, and were processed for histological and immunohistochemical examination. In the untreated diabetic group, the islets appeared shrunken with disturbed architecture and abnormal immunohistochemical reactions for insulin, caspase-3, and inducible nitric oxide synthase (iNOS). The biochemical findings were also disturbed. Morphometrically, there was a significant decrease in the islet size and islet number. Treatment with sitagliptin, metformin, and their combination showed an improvement, with the best response in the combined approach. No evidence of pancreatic injury was identified in the sitagliptin-treated groups. In conclusion, sitagliptin had a cytoprotective effect on beta-cell damage. Furthermore, the data didn’t indicate any detrimental effects of sitagliptin on the exocrine pancreas.

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DECREASEMENT OF LYSOPHOSPHATIDYLCHOLINE LEVEL, NF-KB EXPRESSION, INTIMA MEDIA THICKNESS AND IMPROVEMENT OF INSULIN RESISTANCE BY DARAPLADIB TREATMENT: IN VIVO STUDIES OF TYPE 2 DIABETES MELLITUS SPRAGUE-DAWLEY RAT MODEL

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2017.v10i12.19022 ◽

2017 ◽

Vol 10 (12) ◽

pp. 362

Author(s):

Titin Andri Wihastuti ◽

Dinda Zahra Putri Andiyani ◽

Sri Andarini ◽

Teuku Heriansyah

Keyword(s):

Diabetes Mellitus ◽

Insulin Resistance ◽

Type 2 Diabetes ◽

Type 2 Diabetes Mellitus ◽

Rat Model ◽

Intima Media Thickness ◽

Aortic Tissue ◽

Sprague Dawley ◽

Media Thickness

Objective: Lipoprotein-associated phospholipase A2 (Lp-PLA2) is an enzyme with several pro-inflammatory properties that involved in pathogenesis of atherosclerosis, but some investigation shows controversial views regarding its biological role. We examined the effect of selective inhibitor of Lp-PLA2 (darapladib) to the inflammation marker, intima-media thickness (IMT), and insulin resistance (IR) of type 2 diabetes mellitus (T2DM) rat model. This study aimed to measure lysophosphatidylcholine (lyso-PC) in serum and aortic tissue, nuclear factor kappa B (NF-κB) expression, IMT, and IR with darapladib treatment in a T2DM rat model.Methods: 30 Sprague-Dawley rats were randomly divided into normal group, T2DM group and T2DM with darapladib treatment. Induction of T2DM was done by giving high-fat diet and low dose injection of streptozotocin. Blood glucose level and insulin plasma concentration were measured to calculate IR. 8 weeks and 16 weeks after treatment, we compared lyso-PC level, NF-κB expression, and IMT.Results: Darapladib significantly decreased lyso-PC level, NF-κB expression, and IMT at two serial treatments. Darapladib treatment group exhibited significant reduction of IR (0.64±0.11 vs. 2.07±0.16, at 8 weeks; and 0.93±0.08 vs. 6.48±0.55 at 16 weeks) compared with T2DM group.Conclusions: These data suggested that Lp-PLA2 played a role in inflammation process, atherosclerosis, and IR occurring in metabolic disorder.

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Echinops Spp. Polysaccharide B Ameliorates Metabolic Abnormalities in a Rat Model of Type 2 Diabetes Mellitus

Current Topics in Nutraceutical Research ◽

10.37290/ctnr2641-452x.19:106-114 ◽

2020 ◽

Vol 19 (1) ◽

pp. 106-114

Author(s):

Guang Hao ◽

Xiaoyu Ma ◽

Mengru Jiang ◽

Zhenzhen Gao ◽

Ying Yang

Keyword(s):

Diabetes Mellitus ◽

Insulin Resistance ◽

Type 2 Diabetes ◽

Type 2 Diabetes Mellitus ◽

Insulin Secretion ◽

Insulin Receptor ◽

Skeletal Muscles ◽

Insulin Receptor Substrate ◽

Sprague Dawley

This study examined the in vivo effects of Echinops spp. polysaccharide B on type 2 diabetes mellitus in Sprague-Dawley rats. We constructed a type 2 diabetes mellitus Sprague-Dawley rat models by feeding a high-fat and high-sugar diet plus intraperitoneal injection of a small dose of streptozotocin. Using this diabetic rat model, different doses of Echinops polysaccharide B were administered orally for seven weeks. Groups receiving Xiaoke pill and metformin served as positive controls. The results showed that Echinops polysaccharide B treatment normalized the weight and blood sugar levels in the type 2 diabetes mellitus rats, increased muscle and liver glycogen content, improved glucose tolerance, increased insulin secretion, and reduced glucagon and insulin resistance indices. More importantly, Echinops polysaccharide B treatment upregulated the expression of insulin receptor in the liver, skeletal muscles, and pancreas, and significantly improved the expression levels of insulin receptor substrate-2 protein in the liver and pancreas, as well as it increased insulin receptor substrate-1 expression in skeletal muscles. These two proteins play crucial roles in increasing insulin secretion and in controlling type 2 diabetes mellitus. The findings of the present study suggest that Echinops polysaccharide B could improve the status of diabetes in type 2 diabetes mellitus rats, which may be achieved by improving insulin resistance. Our study provides a new insight into the development of a natural drug for the control of type 2 diabetes mellitus.

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Role of TLR4/MyD88/NF-κB signaling in heart and liver-related complications in a rat model of type 2 diabetes mellitus

Journal of International Medical Research ◽

10.1177/0300060521997590 ◽

2021 ◽

Vol 49 (3) ◽

pp. 030006052199759

Author(s):

Jiajia Tian ◽

Yanyan Zhao ◽

Lingling Wang ◽

Lin Li

Keyword(s):

Diabetes Mellitus ◽

Type 2 Diabetes ◽

Type 2 Diabetes Mellitus ◽

Signaling Pathway ◽

Rat Model ◽

Fasting Blood Glucose ◽

Diabetic Rats ◽

Primary Response ◽

Monocyte Chemoattractant Protein 1

Aims To analyze expression of members of the Toll-like receptor (TLR)4/myeloid differentiation primary response 88 (MyD88)/nuclear factor (NF)-κB signaling pathway in the heart and liver in a rat model of type 2 diabetes mellitus (T2DM). Our overall goal was to understand the underlying pathophysiological mechanisms. Methods We measured fasting blood glucose (FBG) and insulin (FINS) in a rat model of T2DM. Expression of members of the TLR4/MyD88/NF-κB signaling pathway as well as downstream cytokines was investigated. Levels of mRNA and protein were assessed using quantitative real-time polymerase chain reaction and western blotting, respectively. Protein content of tissue homogenates was assessed using enzyme-linked immunosorbent assays. Results Diabetic rats had lower body weights, higher FBG, higher FINS, and higher intraperitoneal glucose tolerance than normal rats. In addition, biochemical indicators related to heart and liver function were elevated in diabetic rats compared with normal rats. TLR4 and MyD88 were involved in the occurrence of T2DM as well as T2DM-related heart and liver complications. TLR4 caused T2DM-related heart and liver complications through activation of NF-κB. Conclusions TLR4/MyD88/NF-κB signaling induces production of tumor necrosis factor-α, interleukin-6, and monocyte chemoattractant protein-1, leading to the heart- and liver-related complications of T2DM.

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